Search form

Osprey By the Numbers

Rob Bierregaard was introduced to the Vineyard’s osprey population by Gus Ben David and has been studying the Vineyard’s ospreys since the 1960s. Gus Ben David, around the same time, saw the need for artificial osprey nesting platforms and he and his team have erected 138 osprey poles on the Vineyard and Chappaquiddick over the years. Rob has been banding the ospreys since the 1960s, and in the last seven years has been placing transmitters on ospreys to follow their migratory paths. Rob elicited the help of Dick Jennings as his man on-Island. Dick found he needed help and asked Dave Kolb to lend a hand. Dick Jennings and Dave Kolb have been busy beavers the last couple of weeks. These two men have checked all the osprey poles that have been erected and also nests that have appeared on other structures. If you find an osprey nest on a chimney, tree, or some other place aside from the existing osprey poles, please let us know.

Dick and Dave are similar to Santa’s helpers as they are checking not once but twice to make sure their nest count is correct. The nest checkers found two new pairs, one in a tree nest on Crocker Pond in West Tisbury and another in the highlands of Chilmark. So when all was said and done Dick emailed me the following information: “...a total of 79 breeding pairs plus 12 pairs of housekeepers.”

I always ask Rob Bierregaard or Dick Jennings how these numbers compare to other years. Rob and Dick agreed with the following: “Looking back at my records, the least pairs (of ospreys) were in 2007 when only 60 pair could be accounted for.” And, they responded that in 2012 there were 78 pair. Therefore, the 79 pair for this year is a new record! It is interesting to note that in 1969 there were only two pair of ospreys nesting on-Island.

Dick added that although we have a bumper crop of adult ospreys, we may not have a record number of fledgling ospreys as the spring weather has been chilly, in case you hadn’t noticed. Cold weather isn’t the best for incubation, especially if the birds are disturbed and come off their nests frequently. Dick Jennings and Dave Kolb will be checking on the number of fledging ospreys these 79 pair produce later in the summer. The results will be printed in the Bird News.

I spoke with Rob Bierregaard briefly and he is on the road tagging osprey with satellite transmitters. He has fitted 82 ospreys with these transmitters from many locations on the East Coast. We have been watching their movements for several years and you can too by going online to Rob’s website ospreytrax.com. Dick Jennings emailed me the following on the Vineyard’s tagged ospreys: “Belle, our 4-year-old star, has yet to settle down. While she has spent time here on the Vineyard, she seems content to be a traveler visiting Mattapoisett most recently, but Long Pond in West Falmouth seems to be one of her favorite haunts. This is the water supply for the town of Falmouth. She recently spent two days at Crystal Lake but is now back in Falmouth.”

“Snowy, who is now 3 years old and back for the second time, also seems to like the Falmouth area rather than the Vineyard. (Suppose they are both tired of waiting for the boat?) The last data I have shows him at Parker Road Pond in East Falmouth.”

“DJ, the male from the Poucha Pond marsh nest, is behaving much more like a responsible dad, rather than a deadbeat dad as he was in the two previous years. We anticipate fledglings from that nest this year.”

Rob Bierregaard did mention that there is still a mystery osprey flying around the Island. This bird has a transmitter that is not functioning and we all would like to know which bird it is. If you see this bird, contact us. The antennae for the transmitter sticks up from the back of the bird and can be seen with binoculars at distance or by eye if the bird is close at hand. Rob also added that this year more ospreys are becoming retro as they are choosing trees in which to nest instead of osprey poles. I would wager the Vineyard trees have grown tall enough since the 1960s, so they provide a nice platform for the fish hawks.

I checked with Gus Ben David to try to find out why ospreys use trees and chimneys and other structures when there are nice, unused poles available. Gus answered that it puzzles him and he can’t second guess the ospreys. In some cases Gus noted the trees around the erected osprey poles have grown taller than the pole. Ospreys don’t choose these poles as they need plenty of room to fly in and out of their nests. They need to have an unhampered flight pattern. Also, they need to be able to see possible intruders. Finally, if a tree has grown too close to the osprey pole there is the possibility of a raccoon climbing up the adjoining tree and raiding the osprey’s nest.

Enjoy the Vineyard’s ospreys; many people are involved in helping this fish hawk use the Vineyard as its home.

Bird Sightings:

Last week Lanny McDowell was home alone when he heard the song of a Kentucky warbler while gardening. He went to the house to fetch his camera but by the time he returned outdoors, the bird had flown. Lanny was able to record the song on his cell phone as it continued singing from its now hidden perch. Fast forward to 4 p.m. when Lanny returned to the garden with his camera and found the Kentucky warbler out in the open so he was able to photograph it.

Unfortunately Allan Keith, Flip Harrington and I were not as lucky. We spotted a wren at Cape Pogue that didn’t fit the description of a Carolina wren. The mystery wren had a brown, not rufous, back, and it had an upright brown tail with white edging and its belly was pure white, not light rusty. This Cape Pogue wren also did not respond when we were pishing (making noise to attract birds). We only had one bird field guide with us and after much backing and filling, decided the bird we saw was a Bewick’s wren. The Bewick’s used to be found east of the Mississippi, but now is found primarily in the southwest and coastal west. When we returned home and checked other field guides we firmed up our identification as we saw that the Bewick’s wren had black legs, which our bird did, (the Carolina wren’s legs are yellow/orange). Also, who ever heard of a Carolina wren that didn’t respond to pishing? This bird may not be accepted by the records committee of Massachusetts due to lack of photo proof, but the three of us will have it on our own lists.

Ken Magnuson was thrilled to hear a bobwhite at the Edgartown golf course on May 27. He mentioned that he hadn’t heard one in that area for years!

Larry Hepler watched four American woodcocks — one adult and three youngsters — saunter through his Quansoo yard on May 20.

Lanny McDowell and Jeff Bernier have been busy photographing terns, skimmers and sandpipers at Norton Point. Jeff and Lanny both had shots of a pair of American oystercatchers feeding their three chicks. Lanny had nice shots of a least tern on two eggs, while Jeff got a lovely shot of a pair of roseate terns showing the rosy breast, which they wear only during breeding season. Lanny’s photographs of semipalmated sandpipers, dunlin and sanderlings showed their differences and Jeff’s close up shots of ruddy turnstones showed off that bird’s elegant breeding plumage.

Baltimore orioles are being reported from West Tisbury to Edgartown. Gus Ben David noted that there has been a huge increase of Baltimore orioles state-wide and said it probably was due to a loss of fields and an increase in woodlands.

Wax Iwaskiewicz in Chilmark, and Iya labunka and Wes Craven of 7 Gates mentioned they had scarlet tanager show up between May 17 to May 23. Matt Pelikan heard one out his work window off Lambert’s Cove Road on May 27.

David and Libby Fielder heard a song in their West Tisbury woods, went online to Cornell Laboratory of Ornithology and figured out it was a prairie warbler. Good research Fielders!

Constance Alexander heard several prairie warblers as she visited the State Forest on May 25.